On Mon, 2019-06-03 at 13:04 -0600, Subash Abhinov Kasiviswanathan
wrote:

quoted

quoted

I can't (or won't) comment right now on whether IPA needs its own
netdev for rmnet to use.  The IPA endpoints used for the modem
network interfaces are enabled when the netdev is opened and
disabled when closed.  Outside of that, TX and RX are pretty
much immediately passed through to the layer below or above.
IPA currently has no other net device operations.

I don't really have issues with the patchset underneath the netdev
layer. I'm interested in how the various bits present themselves to
userspace, which is why I am trying to tie this in with Johannes'
conversation about WWAN devices, netdevs, channels, and how the
various
drivers present API for creating data channels that map to
different
modem contexts.

So let me rephrase. If the control plane has set up the default
context
and sent a QMI Start Network message (or the network attached the
default one) and the resulting IP details are applied to the IPA
netdev
can things just start sending data? Or do we need to create an
rmnet on
top to get that working?

Dan

Hi Dan

All data from the hardware will have the MAP headers.
We still need to create rmnet devs over the IPA netdev and use it
for 
the
data path.
The IPA netdev will pass on the packets which it receives from the 
hardware
and queue it to network stack where it will be intercepted by the
rmnet rx handler.

Ok, so IPA only needs a netdev so that rmnet has something to
send/receive packets to/from? This gets even closer to the discussion
in "cellular modem driver APIs - take 2" from last week.

Dan